Japanese Laid-Open Patent Application No. 32415/1992 discloses a loading base in a circulative conveyance which is tilted forward for unloading an article placed on the loading base in an unloading position. As disclosed therein, no matter whether a circulative conveyance path of the loading base is in a horizontal plane or in a vertical plane, the loading base is tilted forward in the unloading position, thereby allowing the article thereon to slide along the upper surface of the loading base for the discharge thereof. Alternatively, instead of tilting the loading base, an endless belt which forms a loading surface is entrained about the loading base and the article thereon is delivered and discharged in the horizontal direction by the rotation of the endless belt.
In the above prior art, when the loading base is tilted, the article thereon is allowed to slide for discharge. The article may be damaged due to a drop impact, and the working atmosphere is deteriorated by the generation of noise due to a drop impact sound. On the other hand, in the case of horizontal delivery and unloading using an endless belt, there is no fear of damage to articles because there is neither sliding nor dropping of the articles, and the generation of noise can be prevented. However, each loading base must be provided with an endless belt driving means to drive the endless belt for the delivery of the article thereon. The mounting of means for supplying power to the belt driving means of the loading base under movement results only a complicated structure of the power supply means and an increase in the size and weight with each loading base. Further, the mounting spacing between adjacent loading bases becomes longer, so the conveyance efficiency is deteriorated. It is necessary to use a conveyor chain to which loading bases are mounted which is large enough to fully bear the weight of the loading bases.